Neurological complications in kidney transplant recipients.

Neurological complications are frequent in renal transplant recipients and may largely contribute to morbidity and mortality. The postransplant neurological complications may be categorized into five areas: 1) Immunosuppressive medications, 2) stroke, 3) peripheral neuropathies, 4) infection, and 5) malignancies. A number of complications are directly caused by the neurotoxicity of immunosuppressive agents. Calcineurin-inhibitors may cause mild symptoms, such as tremors and paresthesia, or severe symptoms, such as disabling pain syndrome and leukoencephalopathy. Severe neurological syndromes may also be caused by the monoclonal antibody OKT3. Stroke may occur in about 8% of renal transplant patients. It may be favored by hypertension, diabetes, and accelerated atherosclerosis which may be acquired during dialysis or after transplantation. Peripheral mononeuritis and polyneuritis may also occur. An acute femoral neuropathy may occur in about 2% of patients as a result of nerve compression after operation. Guillain-Barré syndrome may also develop, triggered in some cases by cytomegalovirus (CMV) or Campylobacter jejuni infection. Lymphomas are the most frequent brain tumors. They are usually associated to a Epstein Barr virus (EBV) infection and are more frequent in patients who received an aggressive immunosuppressive therapy. Infection represents the most frequent neurological complication. Acute meningitis usually caused by Listeria monocytogenes, subacute and chronic meningitis caused by Cryptococcus neoformans, focal brain infection caused by Aspergillus fumigatus, Toxoplasma gondii or Nocardia asteroids, and progressive dementia caused by polyoma J virus or other viruses are the most frequent types of neurological infections.